Prior to the release of storage device VNX2, EMC2® (hereinafter EMC2) released VNX, AX/CX block storage products. However, block storage products, such as VNX, AX/CX may not support a scenario that a user drive or a system drive is moved, that is, those products require all drives to be fixed in their respective drive slots, and the replacement of a drive with a new drive is only allowed when a drive malfunctions or gets damaged.
In EMC2 VNX2 array, a physical drive in the storage system may no longer be required to be bound with a particular slot. Therefore, “a portable drive” may become a features of VNX2 array. In other words, physical drives with bound logical unit numbers (LUNs) and disk groups (Raid groups) (the Raid groups mainly provide data re-establishing, verification and Raid algorithms) may be moved to different slots in a storage system, and meanwhile these drives may still be recognized as those LUNs and Raid groups. The drives and Raid groups/LUNs would keep available during or after a drive movement. Since VNX2 makes movement of physical drives possible, movement of a physical drive should also be transparent to the Raid group when a physical drive is moved to another slot.